I must agree with this method. There is no substitute for researching companies. I'd filter a bunch of 10k's and look for abnormalities etc.. You can start with the typical top down approach - decide what your view is on the economy, pick an industry you think is poised to do well or badly in those circumstances, start filtering firms that fit in with your assumptions. Look for the drivers of revenues and costs for these firms and see if you can find anything that is 'abnormal' and make a play based on those...
I think it is quite interesting. You have a dashboard to monitor/control your online presence. I've done this for a while with my own website, but they are bringing it to the general public.
I'd be curious to know what their business model would be though. I can see that they will be aggregating more user data as they can associate all your online profiles with your one persona now.
I believe you may as well do basic on page SEO when building your site. Maybe even build in a blog, which will serve two purposes - original content and updates for your readers.
You can do link building passively (review posts, guest blog posts etc...).
I do agree with some others that it would be unwise not to do a little leg work from the beginning when building your site.